The Wildlife Institute of India is keeping an eye on the sky to measure the impact on the fragile Himalayan ecosystem from helicopters carrying pilgrims to the holy shrine in the Kedarnath valley during this year’s Char Dham yatra

Nine aviation firms are doing some 300 sorties daily to the shrine from four points —Guptkashi, Sersi, Phata and Maikhanda.(HT File)

The Wildlife Institute of India (WII) is keeping an eye on the sky to measure the impact on the fragile Himalayan eco-system from helicopters carrying pilgrims to the holy shrine in the Kedarnath valley during this year’s Char Dham yatra.

More than 110,000 pilgrims have visited the shrine since May 9, of whom nearly 70% took a chopper ride instead of a 16km trek to the temple complex that was rebuilt after the 2013 tragedy in which a cloudburst-triggered landslide flattened the area and killed many people.

About nine aviation companies were doing some 300 sorties every day to the shrine from four points —Guptkashi, Sersi, Phata and Maikhanda.

It has been alleged that the helicopters are breaking aviation norms by flying too low, thereby increasing the noise level in the valley to more than 120 decibel, which is harmful for humans and animals.

Another area of concern is that the number of sorties has increased with each passing year, though each company was permitted 19 sorties a day since 2010.

“In 2012, there were hardly 20 sorties. This time it is expected to exceed 300. We don’t know the impact on wild animals but regulation is certainly needed to protect the sensitive ecosystem,” said S Sathyakumar, a senior scientist with the WII.

The Kedarnath divisional forest officer in 2013 mentioned in a report that the helicopter noise was upsetting the breeding pattern of musk deer, an endangered species. Increased stress levels in other wildlife were found too.

Apparently, the study wasn’t scientific and so the chief wildlife warden contacted the Dehradun-based WII for a detailed study in 2015.

Since then, the institute has been sending scat samples of wild animals to the Centre for Cellular and Molecular Biology in Hyderabad to ascertain stress levels in wild animals in the region. Fresh samples are being collected after the yatra began this year to study hormonal changes in animals.

“This will let us know if there’s any hormonal change between samples sent in the off season and during the yatra. This will help understand stress levels in animals because of the aviation service,” scientist Sathyakumar said.

Besides, a team of scientists is doing a field study in the valley and the Kali Ganga area — famed for the Asian antelope, leopard, Himalayan goral, Himalayan tahr and jungle cat. But the main concern remains the shy musk deer.

The National Green Tribunal too asked the Uttarakhand government in 2015 to conduct a scientific study on the impact on wild animals from the helicopters after the Doaba Paryavaran Samiti, an NGO, moved the green watchdog. The WII was approached for the task later.